Calculation And Simulation Design Of Linear Induction Motor Electromagnetic Performance

At the present day, urban traffic is becoming worse increasingly. Development of urban wheel-on-rail transportation systems is urgent to solve the urban traffic problems. The linear motor is a new driving type of urban rail transit system and the research on linear motors has become the focus currently. The linear motor is a kind of gearing which can transform electrical energy directly into linear moving mechanical energy without any middle conversion device. Comparing with the transmission form of "revolving machine mechanical converter", the linear motor has obvious advantages: such as simple structure, no contact or abrasion, low noise, high speed, high accuracy and so on.As the rotor of linear induction motor is of such some characters as cut-off ends, big air-gap length, and so on, its performances are largely different from general rotary motor even if they are of the same working theory, efficiency, power factor and starting performance are all much lower than general rotary induction motor. But the linear induction motor has many advantages such as simple structure, high mechanic reliability, high control accuracy, directly driving linear motion, and so on. which make linear induction motor to be wide use in many fields, especially in Urban traffic system. Linear induction motor will play a great important part in traction, and absolutely replace the rotor induction motor. So, it is very necessary to do research on LIM. In this paper, more attention is paid to the analysis on end effect and electromagnetic performance of the single-sided linear induction motor(SLIM).The foundation theory and property of the Linear Induction motors is introduced firstly. Theoretical analysis on all kinds of end-effects of SLIM is given. Effect on performance by secondary material is introduced. Then, based on the analysis of the different structure between linear induction motor and rotary induction motor (RIM), referring to the research method of RIM, we get a complete equivalent circuit, considering end effects of LIM, and use MATLAB to calculate the steady-state characteristic of LIM. We get curve of SLIM's thrust force, efficiency and power factor with the different current and its frequency, air gap, secondary structure and velocity . This paper simulates LIM by Maxwell 2D, and it's structure parameter and running performance is focused on. In the end, the design of LIM's dimensions is introduced.